//
//  CZDismissAnimation.swift
//  GZWeibo007
//
//  Created by Apple on 15/12/31.
//  Copyright © 2015年 Apple. All rights reserved.
//

import UIKit

/// 控制关闭时的动画
class CZDismissAnimation: NSObject, UIViewControllerAnimatedTransitioning {
    // 转场时间
    func transitionDuration(transitionContext: UIViewControllerContextTransitioning?) -> NSTimeInterval {
        return 0.25
    }
    
    // 实现动画
    func animateTransition(transitionContext: UIViewControllerContextTransitioning) {
        // 1. 获取到modal出来的控制器的view
        let fromView = transitionContext.viewForKey(UITransitionContextFromViewKey)
        
        // 2. 做动画
        UIView.animateWithDuration(transitionDuration(transitionContext), animations: { () -> Void in
            // 注意: s缩放的Y值不能写0,如果填0就没有动画效果了
            fromView?.transform = CGAffineTransformMakeScale(1, 0.0001)
            }) { (_) -> Void in
                // 告诉系统关闭的转场动画完成了
                transitionContext.completeTransition(true)
        }
    }
}
